Deadlocking latch



April 24, 1951 E. M. MILLER DEADLOCKING LATCH 2 Sheets-Sheet 1 FiledMarch 11, 1948 April 1951 E. M. MILLER DEADLOCKING LATCH 2 Sheets-Sheet2 Filed March 11, 1948 avvewrm [ow/m0 M MILLER g %&D0W ATTOHNEYJPatented Apr. 24, 1951 DEADLOCKIN G LATCH Edward M. Miller, Kent, Ohio,assignor to The C. L. Gougler Machine Company, Kent, Ohio,

a corporation of Ohio Application March 11, 1948, Serial No. 14,342

and eificient dead locking bolt for a lock of the 5 character indicated,utilizing novel and improved dogging leverage means.

Other objects and advantages will be apparent from a study of thefollowing description in conjunction with the accompanying drawings, in1 which:

Fig. 1 is a horizontal section through a fragmentary portion of a doorand door J'amb, illustrating a dead locking latch bolt embodying myinvention;

Figs. 2, 3 and 4 are sectional views taken respectively on the lines2-2, 3-3 and 4-4 of Fig. 1;

Fig. 5 is a view similar to Fig. 4 but with certain portions cut away orremoved to illustrate internal structure;

Figs. 6 and 7 are views similar to Fig. 5, but showing differentoperating positions of some of the movable elements;

Fig. 8 is a sectional View taken on the line 88 of Fig. 1;

Fig. 9 is a View similar to Fig. 8 but showing different operatingpositions of some of the movable parts; while,

Fig. 10 is an exploded perspective view of a number of the operatingelements of my novel and improved dead locking bolt.

In the following description the terminology dead locking bolt comprisesa lock bolt normally urged to locking engagement with a keeper,

and having means preventing its forcible disen gagement with saidkeeper, said means however being rendered ineffective to prevent normalretraction of the bolt by operation of the inner door knob. The bolt maybe retracted by means of the outer door knob after suitable releaseoperation of a lock.

A bolt of the character just mentioned may be used in conjunction withany of the usual outer door locks for residences, or the like, althoughI prefer a lock mechanism such as illustrated and described in mycopending application, Serial No. 14,341, filed March 11, 1948. Suchmechanis-mis shown only in outline herein, there being a fragmentaryshowing in Fig. 1 of a bolt retracting means 20 to which is affixed apin 2!. It will be understood that appropriate rotation of inner knob22, for example, produces movement of pin 2| to the left so as towithdraw bolt head 23 from keeper aperture 24 whereby the door 25 may beswung away from jamb 26.

The means whereby motion of link 29 is transmitted to latch bolt 23, andthe means for deadlocking the latch bolt, will now be described.

The edge of door 25 is provided with an inwardly extending aperture 27in which is fixed a tubular bolt housing 28, outwardly flanged at itsperiphery 29 and secured to the door by a face plate 30 in conventionalfashion (Figs. 1, 2 and 5). The door jamb carries a striker plate 33having an aperture therein in alignment with keeper aperture 24. Innormal operation, when the door is closed, bolt 23 is cammed toretracted position by the leading edge 33a of the striker plate, andspring 34 biases the bolt to door looking position in keeper aperture24.

The bolt, and cooperating dead locking means are clearly shown inexploded perspective in Fig. 10, and in various working positions inFigs. 2 to 9.

The latch bolt is provided with a beveled leading face 35, a flattrailing face 36, a stop flange 31 which is maintained in normalabutment with face plate 30 by spring 34, and a pair of rearwardlyextending shoulders 38 to which is attached the mechanism for operatinga dead locking lever or slider 39. A base plate 46 is attached toshoulders 38 by screws, rivets or otherwise. The base plate might beintegral with the bolt head, but may be more readily fabricatedseparately. Base plate 40 carries three posts 43, 44 and 45. Near theirtips posts 43 and 44. have portions 43a and 44a of reduced diameter, theshoulders thereby provided serving to support a top plate 45, spacedsomewhat from base plate 49, and in fixed relationship thereto. A doglever 4'! and a dog release link 48 are housed between base plate 48 andtop plate. The dog lever is perforated at 45. to receive post 44, and bepivoted thereon for limited outward swinging movement, as indicated forexample in Figs. 7 and 9. Outward swing of dog 41; is limited by contactof tip 470. of the dog with.

a tab 40a on base plate 42. Tabs 40a and 40b likewise serve as supportsand spacers for the front end of plate 46. Post 45 on base plate 4!!carries a spring 53 the free end of which abuts a finger 411) on dog 41,and normally biases the finger end 4112 inwardly, and the tip end 4111outwardly.

The dog release link 48 lies in the same plane and adjacent to'dog 41.Link 48 has a lost motion connection with plate 48, the link being cutaway at 48a to receive post 43, and the cut away recess being somewhatlonger than the diameter of post 43, so as to permit limited endwisemovement of link 48. The edge portions 410 and 480 of dog 41 and link 48respectively (Figs. 8, 9' and lie adjacent each other. In the positionof Fig. 8 the shoulder 41d of the dog is longitudinally aligned with theinturned rear wall 28a of housing 28. When so aligned, the bolt cannotbe retracted, even forcibly with a jimmy, but the aperture 281) in rearwall 28a is large enough to permit retraction of the bolt assembly whendog shoulder 41d is in the position shown in Fig. 9.

Referring to Figs. 1, 8 and 9, pin 2| is operatively connected to thedoor knob, and seats in aperture 5| in link 48. Movement of link 48 tothe of spring 53, so as to draw shoulder 47d inwardly to the Fig. 9position. When the aforesaid lost motion is taken up, the whole boltassembly is retracted, and the bolt head 23 is freed from the keeper.

The bolt mechanism so far described permits retraction of the bolt onlyby means of the outer or inner knob, and the door could be closed onlyby turning the knob and keeping it in the turned position until the bolthead registers with the keeper. To permit the door tobe closed by asimple slamming motion, a dead lock slider control, herein termed a deadlock lever 39, is provided which in certain operative positions iseffective upon dog 4'! to keep it swung inwardly, so that the door maybe pulled or pushed to fully closed position without turning the knob.

Lever 39 has a short body portion 39a, an inner leg 39c and an outer leg3%. The outer leg 38b passes through a slot 31a in stop flange 31 andrides on the flat face 36 of theh bolt head 23.

The inner leg 39c rides on the exposed face of top plate 46 being guidedbetween two tabs 46a on the plate. As best seen in Figs. 1 and 4, thebody portion is normally biased against stop flange 3? by a helicalspring 52 the ends of which are telescoped on projections 54 and '55carried respectively by wall 28a of the housing, and by the body 39 ofthe dead lock lever.

While the door is in the open position, as best seen in Figs. 4 and 5,the body 39a obstructs the tip file of dog 47 so as to prevent spring 53from swinging dog '41 to dogging position. As long as the dead locklever is in this position the bolt can be freely cammed inwardly as forinstance by slamming the door. When the door is slammed, however, thebolt head 23 and dead lock lever 39 are cammed inwardly by striker plate33. When the door comes to a stop against the stop bead 26a. on jamb 26(Fig. 1) the bolt head 23 snaps outwardly into keeper aperture 24, butthe dead lock lever 39 is still blocked by the striker plate, so thatall parts of the bolt. assembly move to the right with respect to thedead lock lever. As soon as finger 41b clears the body 39a of lever 39,it snaps inwardly under leg 3% and the parts assume the position shownin Fig. '7, the shoulder 41d of the dog 41 moving outwardly to doggingposition. In such position the bolt cannot be forced inwardly. The boltmay however be retracted by operation of the retracting link 48 by theknob, the dog being thereby pulled inwardly by cam action of the edgefaces 41c and 480 as heretofore explained,

during which action spring 52 advances the body portion 39a of lever 38so that it. again holds dog 41 out of dogging position until the door isagain closed.

' of the dead lock lever 39 From the preceding description it will beapparent that without dead lock lever 39, dog 41 would be at all timeseffective to block forcible retraction of the bolt head in any wayexcept by operation of the door handle. The interposition permits thebolt head to be cammed inwardly at any time except when the bolt head isin thekeeper aperture while the dead lock lever is intercepted by thestriker plate.

In the drawings, Fig. 5 shows the bolt and dead; lock lever positionwhen the door is swinging freely; Fig- 6 shows the parts when fullyretraoted by the door knob; Figs. 1 and 7 show the parts. when the, bolthead is in the keeper aperture, but the dead lock lever is held back bythe striker plate.

What I..claim is:

1. A dead locking night latch mechanism for a latch bolt which isspring-biased forwardly to seat in a keeper aperture in, a door jamb,said mechanism comprising a housing, a bolt retractor link having a lostmotion connection with said bolt including a post connected with saidbolt and a recess in said link embracing said post and wider than thediameter of said post, a 105; pivotally carried on said bolt and havinga free end biased to swing away'from said bolt into a bolt blockingposition engaging a portion of said housing whereby to prevent rearwardretraction of saidbolt, a dead locking, lever slidaloly movableforwardly and rearwardly on said bolt but normally spring biasedforwardly, said lever when in forward position being in engagement, withsaid dog. and eifective upon said'd'og. to prevent said dog, fromassuming bolt-blocking position, said dead locking lever being disposedto operatively abut. the edge of said keeper aperture when said boltenters said, keeper aperture whereby to move said lever rearwardly uponand relative to said bolt, and out of engagement with said dog tothereby permit the dog. to. blockv forcible retraction of said bolt,said, retractor link and said dog lying, adjacent each other and havingcomplementary edge face portions; of cam-like character disposed to bebrought into operative contact with each other while saidv link is beingrearwardly retracted to take. up said lost motion, said operativecontact and. continued rearward movementv of said link relative to said.bolt causing said dog to be-swung inwardly from. bolt-blocking position.

2. A dead locking. night. latch mechanism for a, door-mounted latch boltwhich. is. spring biased to seat in a keeper aperture. in av door jamb,said. mechanism comprising, a door-knob-operated part, a. bolt retractorlink connected to said part and having a lost motion connection withsaid bolt. including a post. connected with said bolt and a. recess insaid link embracing said post and wider than the diameter of said post.a dog pivotally mounted on said, latch bolt, a spring normally biasingsaid dog towards a bolt.- blocking position, said dog and said linklying adjacent each other and having com lementary edge portionsdisposed to be brought, into operative abutment by rearward motion ofsaid. link relative to said bolt while taking up. said lost motion, andeffective upon such abutment. to move said dog from bolt-blockingposition and to permit retraction of said bolt, a dead lock. leverextended with said bolt when said door is open and depressed by saidkeeper when. said door is closed, said dead lock lever when extendedeffective upon said dogto prevent its spring biasing said dog tobolt-blocking position, and said dead lock lever when depressedeffective upon said dog to permit its spring to bias said dog tobolt-blocking position, whereby when said bolt is in door lockingposition in said keeper, said 5 bolt cannot be forced out of said keeperexcept by rearward retraction of said link.

EDWARD M. MILLER.

6 REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 812,871 Papefoth Feb. 20, 19061,133,962 Hoglund Mar. 30, 1915 1,164,743 Musselman et a1. Dec. 21, 19151,876,080 Schlage Sept. 6, 1932

